History is missing when I search

When I search something that I visit frequently in my history, my results skip about a whole month. My results go back to July 29th, and the next date is June 30th. Again, this happens in searches for websites I visit every day, like Facebook and Youtube, but not when I search something in the history that I only visited maybe once or twice during that block of time. When I search something that I visited infrequently, I get accurate results, showing dates, including when I accessed them during that month.

My full search history for that whole month is accessible if I just go into the history and keep clicking "older" (or when I replace the page number in the address bar with a higher number and hit Enter) but not when I actually run the search.

I was trying to find a video that I had watched on YouTube last month, and that's when I noticed that there was this huge block that it either wasn't searching or wasn't producing results for. Does anyone know what's wrong, or even just a workaround, rather than going through every page, doing a "Find"?

Tip: For the really important bookmarks open Windows Explorer and create a bookmarks folder. Drag all URLs in there for a backup. Then back that up on a flash drive. As you have seen, browsers cannot always be trusted with bookmarks and passwords. Type all of your account urls, usernames, and passwords into a text file for safe keeping. Mine is about 50kb. Back that up on a Flash Drive etc.